prevent accidental changes to storage structs #533
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sam0x17
changed the title
sam0x17
requested review from
orriin,
distributedstatemachine,
open-junius,
keithtensor and
a team
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Look good! I have a question, how to get the hash value in freeze_struct()? |
from the compile error |
sam0x17
added
blue team
| @@ -0,0 +1,7 @@ | |||
| use subtensor_macros::freeze_struct; | |||
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| #[freeze_struct("ecdcaac0f6da589a")] | |||
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How can one calculate this hash in an easy way?
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so right now the dev ux is basically you are in one of two scenarios:
- you are adding it to a new struct, in which case you just do
#[freeze_struct]with zero args and the compiler error will immediately tell you the proper hash code - you are updating an existing struct that already has a hash code, in which case the compiler error the second you change the struct will tell you the new expected hash code, and also encourages you to write a migration etc. if applicable
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people running RA will see it literally in their IDE as well
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also worth noting it is immune to doc comment changes, they aren't part of the hash code calculation, and arbitrary additional nodes to ignore could also be added to the visitor pattern if desired
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I see, that's cool! but will this work also for generic structs? It seems like it will also break if you rename a generic or field, even if it is the same encoding?
I think it is certainly a cool idea, and if no similar rust crate exists, we can make it an independent Rust crate, and reference it in our docs.
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Yeah it could be modified to be immune to name changes. I wasn't sure if that was safe in all cases so I left that out of this one
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Same goes for generics, whatever you want it to ignore in the hash code calculation can be added to the visitor pattern
| @@ -139,7 +139,7 @@ pub const VERSION: RuntimeVersion = RuntimeVersion { | |||
| // `spec_version`, and `authoring_version` are the same between Wasm and native. | |||
| // This value is set to 100 to notify Polkadot-JS App (https://polkadot.js.org/apps) to use | |||
| // the compatible custom types. | |||
| spec_version: 154, | |||
| spec_version: 155, | |||
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Should we just leave this unchanged?
Fixes #513
devnet companion: #550, #554